diff --git a/eslint.config.mjs b/eslint.config.mjs
index c85fb67..0956066 100644
--- a/eslint.config.mjs
+++ b/eslint.config.mjs
@@ -11,6 +11,27 @@ const compat = new FlatCompat({
 
 const eslintConfig = [
   ...compat.extends("next/core-web-vitals", "next/typescript"),
+  {
+    rules: {
+      // #495: this codebase has no components/ui barrel file today — every
+      // component is already imported directly by filename. This rule keeps
+      // it that way by rejecting any future `@/components/ui` (or a nested
+      // barrel under it) import before it can reintroduce the tree-shaking
+      // problem #495 was filed against.
+      "no-restricted-imports": [
+        "error",
+        {
+          patterns: [
+            {
+              group: ["@/components/ui", "@/components/ui/index"],
+              message:
+                "Import directly from the component's own file (e.g. '@/components/ui/Button'), not a barrel — barrel imports defeat tree-shaking (#495).",
+            },
+          ],
+        },
+      ],
+    },
+  },
 ];
 
 export default eslintConfig;